The development of research on human genetic variation, including the identification of single-nucleotide polymorphisms (SNPs), may create new relationships between genetic diseases or conditions and current concepts of race, ethnicity, and culture. The result may be an increased risk for stigmatization for populations implicated in these findings. The recent experience of Ashkenazic Jews and BRCA1/2 testing and community complaints about stigmatization, gives substance to these concerns. Previous research has focused more on discrimination rather than stigmatization or on "single-gene" conditions, such as cystic fibrosis or sickle cell disease. These studies provide a useful, but limited perspective from which to anticipate the future. The potential impact of research on human genetic variation calls for a more systematic and comprehensive understanding of the factors people bring to bear in interpreting genetic difference and conditions that may encourage stigmatization. To assure that this understanding is comprehensive and that it can effectively address social concerns about genetics research, it must include the perspective of the scientists who conduct this research. The proposed project will determine the factors with which people distinguish genetic from non-genetic disease, and the factors that they bring to bear in interpreting genetic diseases or conditions. The project will identify the ways in which these factors might vary between the following three contrastive pairs: 1) people who are members of racial or ethnic groups that historically have been subjected to stigmatization, versus those who are not; 2) scientists who conduct this research, and the lay public who it may concern; and, 3) people who have a known genetic condition, and those who do not. We will explore these questions with two studies: Study 1 is a face to face guided interview that includes open-ended questions and card sorts; Study 2 is a questionnaire, that includes a Social Stigma Scale and an Attribution of Genetic Difference Scale. The project goals are to determine the variety of factors people bring to bear on interpreting genetic conditions, the circumstances that encourage stigmatization, and to test the hypothesis that stigmatization occurs more often among people who are members of populations that are already stigmatized.